1Universitätsmedizin Göttingen Herzzentrum, Klinik für Kardiologie und Pneumologie Göttingen, Deutschland
Background
As transcatheter aortic valve replacement (TAVR) in patients with severe aortic stenosis (AS) is gaining importance, accurate risk stratification is crucial to improve patient selection and overall procedural safety. While epicardial adipose tissue (EAT) has already been shown to have great implications in cardiovascular disease, its impact on patients with severe AS undergoing TAVR patients has yet to be validated.
Methods
A total of 416 patients with severe AS were assigned for TAVR at the University Medical Center Göttingen, and prospectively enrolled for systematic assessment. Patients underwent structured clinical surveys and 5-year long-term follow-up, with all-cause mortality as the primary endpoint. Patients were diagnosed and graded by echocardiography following guideline recommendations. EAT was calculated on pre-TAVR planning CTs using semiautomated contouring to outline the pericardium and quantify tissue volume between -190 to -30HU. Patients were dichotomized at the median of 74cm3 of EAT into a low EAT and high EAT group to perform further analysis. Mortality rates were compared using Kaplan-Meyer plots and uni- as well as multivariable cox regression analyses.
Results
A total number of 341 of 416 patients (median age 80.9 years, 45% female) could be included in the final analysis. Patients within the high EAT group had higher NYHA stages as well as higher aortic calcium scores compared to the low EAT group. Patients with high EAT had similar short-term 30day outcome (p=0.794) compared to patients with low EAT. However, they revealed significantly worse long-term outcome (p=0.023). No differences in post-TAVR conduction abnormalities could be observed. Increased EAT was associated with worse long-term outcome (HR1.59 p=0.031) independently from concomitant cardiovascular risk factors and general type of AS, as well as independently from echocardiographic parameters characterizing the AS (HR 1.69; p=0.013).
Conclusion
Increased EAT volume is an independent predictor of all-cause mortality in patients with severe AS undergoing TAVR. It can be easily and reliably quantified from pre-TAVR planning CTs and may thus qualify as an innovative marker to improve prognostication and management of patient with severe AS.